Wrong Kit Dispensed After Randomization in a Blinded Trial
At Site 045, a double-blind placebo-controlled trial uses an interactive web response system (IWRS) for randomization and kit assignment. At Visit 2, Subject 045-011 was randomized to Arm B, and IWRS assigned kit 045-011-0032. The site pharmacist dispensed kit 045-011-0041, which IWRS records as Arm A, because the pharmacist misread the last two digits. The subject received one dose from the wrong kit and returned two weeks later for the next visit. The error was discovered when you reconciled the dispensing log with IWRS. The subject has had no serious adverse events but reports mild dizziness. The pharmacist says, 'If we tell anyone, we may have to unblind the subject, and then the data are ruined.' The site proposes to continue the subject on the same wrong kit for the rest of the study to maintain consistency and avoid unblinding. The investigator has not been informed. The sponsor's medical monitor is available by phone.
1. What immediate actions should you take, and should the subject continue on the wrong kit?
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Stop further dispensing from the wrong kit, quarantine the remaining wrong kit, and inform the investigator and sponsor medical monitor. Do not continue the subject on the wrong kit just to maintain consistency. The subject received one dose of the wrong treatment; the priority is safety and accurate data, not preserving blinding at the cost of a known error. Obtain details of the dizziness: onset, duration, vital signs, concomitant medications, and whether it resolved. Verify the IWRS assignment and dispensing log for all subjects at the site, because this may not be an isolated error. Ask the pharmacy to secure the correct kit 045-011-0032 if still available. The medical monitor and investigator should decide whether the subject receives the correct kit at the next dose or is withdrawn, according to the protocol.
2. How should unblinding be handled, and what should you tell the pharmacist?
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Unblinding should be limited and justified. The subject already received a known wrong kit; continuing on that kit does not restore the blind. The medical monitor and investigator should decide whether unblinding the subject's treatment assignment is necessary for safety. If unblinding occurs, document who was unblinded, why, and how the subject's future data will be handled. Often the subject can continue in a modified way, but the protocol and sponsor must decide. Tell the pharmacist that the concern about 'ruining data' is secondary to subject safety and trial integrity. Hiding the error would be worse because it would leave unacknowledged wrong treatment and unreliable data. The CRA should not let site staff pressure them to conceal the deviation.
3. What reporting and corrective actions are needed?
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Report as a protocol deviation and potential serious breach because wrong IP administration can affect safety and data integrity. Notify the sponsor immediately, the IRB according to policy, and document all notifications. Root causes to examine include look-alike kit numbers, manual transcription, lack of independent double-check, and no reconciliation at dispensing. Corrective actions should include second-person verification of the kit number against IWRS, separation of adjacent kit numbers in storage, label checks, and staff training. Audit other subjects at the site for similar errors. Follow up at the next visit and confirm the subject's safety and the plan for data handling. The site should provide a CAPA with evidence of implementation, not just an apology.